In a cellular mobile telephone or wireless communication device including a plurality of reception/transmission circuits, the digital interfaces normally generate interference which adversely affects the radiofrequency transmitters and which causes a degradation in the received signals and therefore a degradation in the receive performance. These digital interfaces are regarded as “aggressors.”
The digital audio signal transmitters/receivers generate interference, notably due to electromagnetic leakage. FM radio receivers are very sensitive to this electromagnetic leakage because, inter alia, FM radios operate at quite low frequencies, notably between 65 and 108 MHz.
FM radio receivers are not the only “victims.” In fact, 2G and 3G transmitters and/or receivers are also potential victims, as is the GPS (Global Positioning System) network, but also phase locked loops, denoted PLL, amplifiers, analog/digital or digital/analog converters, etc.
More generally, any electronic device containing sensitive analog parts may fall victim to interference.
The 2G or 3G bands are higher. The minimum lower limit of these bands has a frequency of 450 MHz. Consequently, interference should not be as great. However, this interference may nevertheless cause serious problems for signal reception.
Moreover, digital audio interfaces may be considered as aggressors for some electronic devices which are then considered as potential victims.